diff --git a/pkg/model/github_context.go b/pkg/model/github_context.go
index 577cab5..e9918a8 100644
--- a/pkg/model/github_context.go
+++ b/pkg/model/github_context.go
@@ -98,7 +98,7 @@ func (ghc *GithubContext) SetRefAndSha(ctx context.Context, defaultBranch string
 		ghc.Ref = ghc.BaseRef
 		ghc.Sha = asString(nestedMapLookup(ghc.Event, "pull_request", "base", "sha"))
 	case "pull_request", "pull_request_review", "pull_request_review_comment":
-		ghc.Ref = fmt.Sprintf("refs/pull/%s/merge", ghc.Event["number"])
+		ghc.Ref = fmt.Sprintf("refs/pull/%.0f/merge", ghc.Event["number"])
 	case "deployment", "deployment_status":
 		ghc.Ref = asString(nestedMapLookup(ghc.Event, "deployment", "ref"))
 		ghc.Sha = asString(nestedMapLookup(ghc.Event, "deployment", "sha"))
diff --git a/pkg/model/github_context_test.go b/pkg/model/github_context_test.go
index f321f53..5cffcde 100644
--- a/pkg/model/github_context_test.go
+++ b/pkg/model/github_context_test.go
@@ -46,7 +46,7 @@ func TestSetRefAndSha(t *testing.T) {
 		{
 			eventName: "pull_request",
 			event: map[string]interface{}{
-				"number": "1234",
+				"number": 1234.,
 			},
 			ref: "refs/pull/1234/merge",
 			sha: "1234fakesha",